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Ataxia Telangiectasia (A-T)

Ataxia telangiectasia (ah-TAX-ee-uh tel-AN-jeck-TAY-zhuh) is a rare childhood disease that affects the nervous system and other body systems. It is an inherited disease. The symptoms of A-T usually begin to show up by age 5.

What causes A-T?

A-T is caused by changed (mutations) in a gene on chromosome 11. The gene is called the ATM gene. It helps control cell division.

A-T is an autosomal recessive disorder. This means that both parents must pass on the mutated ATM gene for their child to have the condition. People with only one ATM mutation are "carriers" of the disease, but they do not have any symptoms of it.

Some studies have found that people who are A-T carriers may have a higher risk for breast cancer, but this link is not clear. About 1 in 100 people in the U.S. are A-T carriers. More studies are being done to better understand this possible link.

What are the symptoms of A-T?

Symptoms of A-T can develop in early childhood. But they may not show up until adolescence or adulthood. Symptoms may include:

Poor balance and slurred speech

Lack of muscle control (ataxia). This causes an awkward gait when walking.

Tiny red “spider” veins (telangiectasias) in the corners of the eyes or on the ears and cheeks. These veins show up soon after the walking problem starts.

Other problems that may occur with A-T include:

Weakened immune system

Increased risk for leukemia

Increased risk for lymphoma

Extreme sensitivity to radiation such as from X-rays

The symptoms of A-T may look like other health conditions. Make sure your child sees his or her healthcare provider for a diagnosis.

How is A-T treated?

There is no cure for A-T. It is managed by treating the symptoms and giving supportive care. Treatment for A-T may include: